Milling machine for copying or profiling



Dec. 5, 1939. H. F. ATKlNs MILLING MAICHINE FOR COPYING OR PROFILINGFiled Sept. 2l, 1938 4 Sheets-Sheet l Figi Harri! Frederik TK'IN s nInventor edn Attorney 51 Fi .2am

[L iLa Dec. 5, 1939. H. F. ATKlNs MILLING MACHINE'FOR COPYING ORPROFILING Filed Sept. 21, 1938 4 Sheets-Sheet 2 Inventor by mi L HarrjFredevmk ATmNs Q21 Aitorney Dec. 5, 1939. H. F, ATKlNs MILLING MACHINEFOR COPYING OR PROFILING Filed sept. 21, 41938 4 sheets-sheet 5 Fig. 9

8 f /l l' 1 g 11 l 9 l 10 r/ ll x vl; L-

In ventor by @f1/WM@ KIQ Attorney Dec. 5, 1939. H F ATKINS I 2,182,331

MILLING MACHINE FOR COPYING OR PROFILING Filed Sept. 21, 1938 4Sheets-snee*` 4 Inventor by WIL; g/ Aiforney y Rmb Fredentk PWKINSPatented Dec. 5, 1939 UNlTED STATES PATENT MILLING MACHINE FOR COPYING RPROFILING Harry Frederick Atkins, 01d Fletton, Peterborough, England 6Claims.

The invention provides the hereinafter described and claimedimprovements in a profile milling or like machine of the kind in which apattern of the shape desired of the article to be machined and the work,on the one hand, and a stylus adapted to be guided by the pattern andthe milling cutter on the other hand, are coupled to effect the desiredoperation on the Work from linear, circular, or combined linear andcircular movements of a carrier upon which the pattern and work arerigidly mounted as one piece, such machine being automatic in its actioneX- cept for hand starting or stopping, and hand application and removalof work.

In particular the invention relates to such a machine in Which thepattern and the work are rigidly mounted' as one piece upon a slidediametrically applied to the face of a carrier-head which is supportedfor intermittent half revolution upon a stationary frame of the machine,the automatic operation of such machine being that while thecarrier-head is held from revolution, that is to say, is heldstationary, the slide traverses, and vice versa. The milling cutter andthe stylus are carried by a common vertically swingable arm to rise andfall together while the stylus contacts the pattern and the cutter,which is revolved independently of all other movements, operates againstthe work.

In previous machines of the aforesaid kind, proiile milling is limitedto contours having angles which such a stylus can effectually negotiateas, for example, angles between 180 and 130 inclusive.

The invention provides a profile milling or like machine of the kind inwhich any angle within 180, and which is reasonably machinable by amilling cutter, can be effectually negotiated under automatic control.

The invention provides a machine of the kind, distinctive by the patternand work being arranged to make automatically independent swivellingmovements in` addition to the automatic movements of the carrier onwhich they are mounted.

More particularly the invention provides a machine wherein the carrieris a slide diametrically arranged upon an intermittently revolublecarrier-head. In this arrangement the work and i pattern are carriedupon a swivelling fulcrumpeg attached to the slide, and the swivellingmovements are automatically arranged for in cooperation with theautomatic relative movements of theslide and carrier-head.

The fulcrum-peg has applied to it a cam-plate (Cl. S30-13.7)

which is acted upon by a plunger to restore the work and pattern backfrom swivelled position to a predetermined normal position relative tothe slide.

Conveniently the fulcrum-peg has applied to it at its forward end thework, the pattern, and the cam-plate, and at its rearward end a rockablelever, the latter to co-operate with abutments on the carrier-head andstationary frame for swivelling the peg.

Hydraulicmeans are preferably applied to the carrier-head for traversingthe slide, and the movement of the pistons is arranged to increase thetraverse of the slide relative to the travel of the pistons.

A machine embodying the essential features of invention in a desirableform is illustratively exemplified in the accompanying drawings, inwhich:

Fig. l is a front elevation looking at the face of the carrier-head.

2 and Fig. 2a are a plan and an edge view, respectively, of the piece ofwork to be profiled.

Fig. 3 is a sectional elevation at right-angles to Fig. l.

Fig. 4 is a view of the assembled fulcrum-peg, rockable lever, cam-plateand pattern.

Fig. 5 is a section of a bearing block for the fulcrum-peg.

Fig, 6 is a front View of Fig. 5.

Fig. '7 is a plan of Fig. 5.

Fig. 8 is a side view of the rockable lever separately.

Fig. 9 is a front elevation of the carrier-head only, on a reducedscale.

Figs. 10-14 are diagrams illustrating the independent swivellingmovements of the pattern and Work, and of the essential parts used forthese movements.

Fig. is a diagrammatic front elevation showing the invention applied toa revoluble carrierhead Without a slide.

With reference to Figs. 1-14, upon a stationary frame i is revolublymounted a carrier-head 2, whose periphery is formed at 3 as a worm wheelto be engaged by a worm 4 Which is suitably driven to revolve saidcarrier-head intermittently a half revolution. Said carrier-head 2 issupported upon the frame I by the roller bearings 5. Except forrevolution said carrier-head is immovable. Abutments G and l are xedupon the stationary frame I, for use as hereinafter described.

The front of the carrier-head is formed with a diametric slide-way 8,and also with a diametric slot 9 at the centre line of the slide-way,while each side said slide-way said carried-head 2 is provided withboundary lugs I0 and II, shown in Fig. 9.

A diametric slide I2 is applied to the slideway 8 to revolve with thecarrier-head 2, but to traverse independently thereof while saidcarrier-head is held stationary. This slide I2 has rigidly connected toit a bearing block I3 where in is provided a clearance hole I4 for arevoluble fulcrum-peg i5, said block being accommodated in the diametricslot 9 of the carrier-head, and extending from the slide I2 rearwardly,and always moving with sai-d slide.

through the slide at the front to engage the block on either side of theclearance hole I4, so that said block is unsupported except by the slideI2.

The fulcrum-peg I5 is anti-frictionally mountlever.

idly mount-ed on the fulcrum-peg I5, and has tralising the position ofthe pattern and work two active surfaces 23 and 24 one thereof on eachside rof the centre line of the slide, a roller 25 carried by a plunger26 operating against said surfaces for the purpose of normallycenrelative to the centre line of the slide, said plunger being urgedinto operation by a strong spring 27, and being guided in its movementby a guide-way 28, arranged centrally of the slide.

f TheV pattern I9 is rigidly clamped onto the forward extension of thefulcrum-peg I5 by a clamping nut 29, (omitted from Fig. 1 for the sakeof clarity), and the work is rigidly clamped to the pattern by means ofscrew pegs and 3I projecting from the face of the pattern I9 and nuts30a and 3Ia screwed onto said pegs, 551

plate 36h. The pattern I9 has a circular idle where necessary withinterposition of a clamping part 32 which acts to lift the millingcutter 33 oi the work, when the stylus 34 is guided by said circularpart, as will be hereinafter explained.

lThe rockable lever 2l fixed to the inner end `of the fulcrum-peg I5 hasreversed stud ends 35, 36, th-e end 35 to operate against a movable stopabutment 3l slidably mounted upon the slide I2, to co-act with theabutment 6, and to 65 inafter described, and the end 36 to co-act withbe operated upon by a spring 38, as will be herethe fixed abutment l, aswill also be hereinafter explained, these abutments serving for theforced rocking of the lever 2I and consequently of the fulcrum-peg I5and the parts it carries.

It is therefore clear that the work I8 is detachably clamped to theformer I9, and the latter firmly and rigidly clamped to the fulcrum-pegI5, as also are the cam-plate 20 and the rockable lever 2|, and that theoscillations Said block is con-` veniently iixed to the slide by screwpins applied` of the fulcrum-peg are caused upon the traverse of theslide I2 and the intermittent rotation of the carrier-head 2, bycooperation of the rockable lever 2I with the abutments 6 and 'I of thestationary frame I and with the movable abutment 3l, all of which willbe hereinafter further made clear.

Within the carrier-head 2 at the back of the slide I2 are arranged twohydraulic cylinders 39 and 40 having complementary double-acting pistons4I, said cylinders being parallel with the slide I2, and disposed oneeach side of its centre line. Each piston is provided with a toothedpinion 42 mounted to revolve upon a diametric pin 43 disposedintermediate of the piston ends, each pinion gearing with opposed racks44 and 45 carried, respectively, on the slide I2 and the carrier-head 2,the pinion and rack gearing being such that the slide I2 is traversed ata ratio of two to one to the movements of the pistons 4I.

At each .of their ends the two hydraulic cylinders communicate by ducts46 and 41 with a liquid passagell controlled by valve action for bothinlet and exhaust of a pressure liquid. by the intermittent revolutionof the carrier-head 2.

A pivotedcatch 49, mounted upon the frame I, normally'holds thecarrier-head 2 from revolving by engagement with one of the boundarylugs I0, I I, said catch being automatically moved out of action uponcompletion of the traverse of the slide I2 by one of the two pegs I2a onthe slide I2 pushing against the stud 49a on the catch 49, after whichthe carrier-head 2 automatically revolves a half revolution from theworm drive until the other lug is automatically engaged by the catch.

The slide I2 always traverses in the same direction, being turn-ed roundby the part-revolution of the carrier-head.

The driving gear for the worm 4 can be a friction gear, instantlystarted and stopped by the release and engagement of the catch 49 inrespect of the lugs I0, II.

The work shown in Fig. 2, is a connecting rod for an internal combustionengine, and the machine is mainly concerned with the automatic machiningof the shoulders 50 and 5I which are approximately at an angle of 90 tothe traverse of the slide I2.

The position of the parts as shown in Figs. 1 and 2 and in the diagramFig. 10 is near the finish of a traverse of the slide I2, while thecarrier-head 2 is held from revolution, up to the commencement of th-emachining of the curved right-angled shoulder 50 of the work, the onestud 35 of the rockable lever 2I being brought into touch with theabutment 31 on the carrierhead 2. The completion of the traverse causesthe abutment 3l, which is for the time being backed up by the xedabutment 6, to rock-said lever 2| and thereby forcibly swivel the workI8 and pattern I9 to enable the shoulder 50 to be inclined for easymachining, as clearly shown by Fig. 1l, this swivelling also forciblymovingr the cam-plate 20 so that the plunger action is operative on oneof the curved rises of said camplate.

The work I8 is now to be moved to bring the other shoulder 5I to thecutter 33, `and this is done by a half revolution of the carrier-head 2without traverse of the slide I2, and While the cutter is idle and thestylus 34 is riding over the idle circular surface 32 at the one end ofthe pattern I9, the carrier-head 2 having been automatically released topermit its drive to operate, during which movement the plunger 26operates upon the cam-plate to bring the Work I8 again onto the centreline of the slide I2, as represented in Fig. 12, this being effectedduring a quarter revolution of the carrier-head 2.

The remaining portion of the idle movement from Fig. 12 to Fig. 13 takesplace during the remaining quarter revolution of the carrier-head 2, andby a swivelling of the Work in consequence of the other stud end of therockable lever 2l contacting the xed abutment 1, while the slide isstationary, so that in relation to the cutter 33 the work I8 has nowbeen mov-ed about three quarters of a circle, to enable said cutter tooperate upon the other shoulder 5l of the work, accomplished by acombined traverse of the slide and the centralising action of theplunger while the carrier-head is held from revolution, this positionbeing shown in Fig. 14, after which the slide l2 makes a simple traverseto the other end of the work, which end is then machined by a simplehalf rotation of the carrier-head while the slide is stationary, afurther traverse of the slide while the carrier is held from rotationvcompleting the circle of operation back to the positions Figs. 1 and10.

The form of the invention shown in the diagram Fig. 15 is one whereinthe revoluble carrierf head 2 is without a slide and has continuous slowrevolution. The work is a cam-shaped piece 52 having a right-angleshoulder 53, against which the milling cutter, and similarly the stylusof the former will not normally' operate, as indicated by the work 52 infull lines, during revolution of said carrier-head, but which bysimultaneously automatically swivelling the work, in accordance with theinvention, to the position indicated in dotted lines 54, said cutterwill automatically operate on said shoulder during the revolution of thecarrier-head.

The carrier for the work and former may be a slide, the invention beingcarried out in connection therewith, for the purpose.

Having now described my invention, what I claim and desire to secure byLetters Patent is:

l. In a prole milling machine, the combination of a movable carrier,means for automatically moving said carrier, a fulcrum peg on saidcarrier adapted for swivelling, means for automatically swivelling saidpeg independently of thesaid peg on the slide with respect to thecarrierhead and slide, a pattern rigidly mounted on the fulcrum peg,means for supporting the work on and coupling it to the pattern to movelas onepiece therewith, a movable stylus to follow the contour of thepattern, and a cutter coupled to the stylus and adapted to operate onthe Work.

3. In a prole milling machine, the combination of a revolublecarrier-head, means for intermittently revolving said carrier-head, aslide diametrically arranged for traverse on said carrier-head, meansfor automatically traversing said slide, a fulcrum peg mounted rotatablyon said slide, means for automatically swivelling said peg with respectto the carrier head and slide, a pattern rigidly mounted on the fulcrumpeg, means for supporting the Work on and coupling it to the pattern tomove as one-piece therewith, a cam-plate rigidly mounted on the fulcrumpeg, a plunger mounted on the slide for cooperation with said cam-plateto normally hold said fulcrum peg in a predetermined angular positionrelative to said slide and to restore it to said predetermined positionWhen it has been swivelled, a movable stylus to follow the contour ofthe pattern, and a cutter coupled to 4. In a profile milling machine,the combination of a revoluble carrier-head, means for in-r termittentlyrevolving said carrier-head, a slide diametrically arranged for traverseon said carrier-head, means for automatically traversing said slide, afulcrum peg mounted rotatably on said slide, a lever mounted rigidly atthe rear end of said fulcrum peg, abutments on the carrier-head andstationary frame With which the rockable lever co-acts to swivel saidpeg upon movements of said carrier-head and slide, a pattern rigidlymounted on the forward end of the fulcrum peg, means for supporting thework on and coupling it to the pattern to move as onepiece therewith, acam-plate rigidly mounted on the forward end of the fulcrum peg, aplunger mounted on the slide for cooperation with said cam-plate tonormally hold said fulcrum4 peg in a predetermined angular positionrelative to the slide and to restore it to said predetermined positionwhen it has been swivelled, a movable stylus to follow the contour ofthe pattern, and a cutter coupled to the stylus and adapted to operateon the work.

5. In a prole milling machine, as claimed in claim 4, a bearing blockincluding bearings for the fulcrum peg and being rigidly attached at oneend thereof to the slide to engage a transverse slot provided in thecarrier head.

6. In a profile milling machine, as claimed in claim 2, a hydrauliccylinder mounted on said carrier-head, a double-acting piston disposedin said cylinder, and a rack and pinion gear connecting said piston withsaid slide to increase the traverse of said slide with respect to thetraverse of the piston.

HARRY FREDERICK ATKINS.

